Experts fear critical phosphorus shortage

To say that phosphorus is critical both to farming and life in general is no understatement. Phosphorus serves a critical metabolic function in plants and animals, helping organisms store and use energy for growth and reproduction. Without it, food production would be impossible.
There are estimates we have as little as 50 years left in the current phosphate mines.
China is buying up as much phosphorus as it can secure from foreign sources, including the United States,
Some experts are even calling for the formation of an international body to monitor the use and recycling of phosphorus.

Jim Langcuster, Auburn University | Oct 18, 2010

A mineral not only essential to farming, but also to life on earth is running out, and scientists currently are at a loss as to what to do about it.

The mineral is phosphorus, which, as The London Times reported two years ago, is being “mined, used and wasted as never before.”

To say that phosphorus is critical both to farming and life in general is no understatement. Phosphorus serves a critical metabolic function in plants and animals, helping organisms store and use energy for growth and reproduction. Without it, food production would be impossible.

Phosphorus is equally as critical to humans, aiding both our metabolism, respiration and building strong bones.

“Plants take it up, we ingest the plants or we ingest animals that ingest other plants,” says Charles Mitchell, an Alabama Cooperative Extension System agronomist and Auburn university professor of agronomy and soils who has followed the growing crisis for several years.

How serious is the phosphorus shortfall?

“There are estimates we have as little as 50 years left in the current phosphate mines,” says Mitchell.

The London Timesreports that “massive inefficiencies” in farm-to-fork food processing coupled with growing Asian demand for meat and dairy produce account for much for the current phosphorus pinch. Spikes in demands for biofuel crops have also contributed.

Much like oil and coal, naturally occurring phosphate deposits are by-products of the death and decay of organisms over millions of years. However, compared with oil and coal, such deposits are rare.

“Because phosphate is so distributed in plants and animals worldwide and so reactive with other elements, you don’t find naturally occurring deposits as readily as you do coal or oil,” Mitchell says.

Florida, Norh Carolina deposits

The richest deposits in North America are found in Florida and in eastern North Carolina, though output from these deposits has dropped by as much as 20 percent in the last few years.

Morocco commands the largest deposits, about 32 percent of the world’s share. Other major deposits are found in Western Sahara, South Africa, Jordan, Syria and Russia.

The Times also reports that a global struggle to secure depleting supplies of phosphorus is already well under way. For example, China, which possesses an estimated 13 billion tons of phosphate rock, has imposed a 135 percent tariff on phosphate rock exports — an action that sent ripples through the world economy.

It’s also buying up as much phosphorus as it can secure from foreign sources, including the United States, Mitchell says.

Skeptics may contend that humans have travelled down a similar road before. In the 19th century, for example, farmers were running critically short of guano, which then served as the primary source of nitrogen fertilizer. At about the time supplies approached depletion, with the specter of food shortages and famine looming, two German scientists stepped forward with a method for extracting nitrogen from the air.

However, phosphorus, by its nature, can’t be synthesized, Mitchell says.

If there is any good news, it’s that phosphorus, unlike energy produced from fossil fuels, isn’t irretrievably lost.

“We can destroy fossil fuels by burning them,” Mitchell says. “But you can’t destroy phosphorus — it’s going to remain in the biosphere somewhere, in plants and animals or in minerals in the soil.”

Likewise, he points to research that has demonstrated consistently that cropland with adequate stocks of phosphorus can remain under cultivation for years, if not centuries, without depletion of these stocks.

“That’s because plants don’t take up nearly as much phosphorus as they do potassium or nitrogen,” Mitchell says.

Even so, Mitchell predicts that effective stewardship of this rapidly depleting resource will become a major worldwide preoccupation over the next few decades.

Consequently, he says that old standby farming methods such as soil testing will take on renewed significance. For that matter, so will precision agriculture, which up to now, has been viewed primarily as a cost-saving measure.

Some experts are even calling for the formation of an international body to monitor the use and recycling of phosphorus.